I just noticed in the "recent badges" section on SO that a few users earned a "C++" and "Java" badge but those badges are not listed on the "Badges" page (which is supposed to show all badges possible. I'm sure that other languages have badges as well, but it leads to the question of what other badges are available that aren't actually listed?
There are "general" and "tags" tabs in the upper-right of the badges page. "C++" and "Java" badges will be listed with the tags.
Those particular badges are created on Demand, they don't exist until someone earns the badge.
Since they aren't like the other badges, they get their own tab.